Plants on the run: Can High Arctic species survive climate change?
Top image: Eike Müller on fieldwork in Recherchefjorden, Spitsbergen. Photo: Pernille B. Eidesen/UNIS
As temperature increases, High Arctic plants need to migrate to find new suitable habitats. Sexual reproduction and dispersal abilities will be critical survival factors. In his PhD thesis, Eike Müller concludes that these plants produce viable seeds and disperse well, thus their fate may not be extinction. Müller will defend his PhD thesis on 16 November at UNIS.
10 November 2011
Press release from UNIS and University of Tromsø
With increasing temperatures, High Arctic plants will be less adapted to current habitats, where they might be ousted by southern species. Recently deglaciated areas can provide new habitats for the High Arctic species, but that depends on their ability to move to new areas and germinate successfully.
Plant migration in the High Arctic is restrained by low temperatures. Nevertheless, earlier studies show that plants settle in deglaciated areas after a while. However, does this affect genetic diversity? From which sources do they disperse and how many individuals are necessary? Is seed dispersal the main strategy for High Arctic plants and how many of these seeds germinate upon arrival? Do plants disperse by “hitchhiking” with travellers to the High Arctic? What can be done to plants which may not be able to “run”?
Successful dispersal and germination
In order to answer these questions Eike Müller has employed molecular methods and germination experiments on samples of High Arctic plants, mostly collected in Svalbard.
He studied mainly if plants may be able to migrate to new suitable habitats if the temperature increases. The germination studies demonstrated that most vascular plant species in the High Arctic produce seeds. This facilitates not only migration. It also means that High Arctic plant species are able to reshuffle their genes, which is an additional path to cope with environmental changes. Many species were found to germinate better than assumed and had a high proportion of vital seeds. However, the germination success in natural conditions was found to be highly influenced by low temperatures.
Molecular analyses of Purple Saxifrage (Saxifraga oppositifolia) showed that plants can migrate to new territories without losing their genetic diversity. The results of the thesis indicated further that not only natural dispersal in the High Arctic is high, also human mediated dispersal to the Arctic is high. Nevertheless, there are possibilities to protect Arctic plant species from the effects of global environmental change. One evaluated option is seed bank storage which can provide a backup for several species.
Eike Müller will defend his PhD thesis “Dispersal and recruitment in the Arctic. Studies of migration and germination in Arctic-alpine vascular plants” on Wednesday 16 November 2011 at 12:30. He will give a trial lecture entitled “Demography in Arctic plant species: key processes from seed dispersal to reproduction” on Wednesday 16 November 2011 at 10:15.
About the candidate
Eike Müller was born in 1973 in Wippra, Germany. He studied forestry and sustainable resource management, specializing in botany and molecular methods.
Müller worked three years in a botanical garden before starting his PhD at UNIS and the University of Tromsø in 2007.
His research interests are in small scale landscape genetics and Arctic-alpine plants.
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